1. Field of the Invention
This invention relates to a connector examination instrument used in the examination of a connector for a wire harness of an automobile, and more particularly to an improved examination pin for detecting an electrical connection of a terminal and an inserted condition of the terminal.
The present application is based on Japanese Patent Application No. Hei. 10-95940, which is incorporated herein by reference.
2. Description of the Related Art
FIGS. 4 to 6 show a connector examination instrument disclosed in Japanese Patent Publication No. Hei. 7-113836. earlier proposed by the Applicant of the present application.
In the connector examination instrument A' shown in FIG. 4, a fixed wall 2, having a wire outlet port 2a, is formed upright at one end of a base plate 1, and an examination instrument body 3 is provided at the other end portion of the base plate 1 for movement toward the fixed wall 2. This body 3 is moved back and forth in accordance with the movement of a pivotally-movable operating lever 5.
A connector support member 6 is provided between the fixed wall 2 and the examination instrument body 3. The connector support member 6 has a frame-like shape, and has a connector receiving chamber 6 which is open at its top and at that side thereof facing the examination instrument body 3. A wire outlet port 6b is formed in that side of the connector support member 6 facing the fixed wall 2. The connector support member 6 is urged toward the examination instrument body 3 by coil springs 8 wound respectively on guide levers 7 extending from the fixed wall 2 into the connector support member 6. When the connector support member 6 is pressed by the examination instrument body 3, the connector support member 6 is moved rearward against the bias of the coil springs 8.
A connector B is inserted into the connector support member 6 from the upper side, and at this time wires W.sub.1 extending from a rear side of this connector, are received in the wire outlet ports 6b and 2a.
As shown in FIG. 5, a plurality of examination terminals 10, corresponding respectively to a plurality of terminal receiving chambers 9 in the connector B, are provided within the examination instrument body 3. An examination pin D', made of electrically-conductive metal, is slidably mounted in the examination terminal 10, and is urged and projected into an examination chamber 13, formed in a front portion of the body 3, by a coil spring 20.
A head 11', having a conducting contact surface 11a, is formed at a distal end of a shank 11e of the examination pin D', and an incomplete insertion-detecting projection 11b is formed at a lower portion of the head 11', and extends forwardly. The shank 11e, the head 11' and the projection 11b are formed integrally with each other, using electrically-conductive metal. Each of the examination terminals 10 is connected to a checker (not shown) via a lead wire W.sub.2 (FIG. 4).
A slanting abutment surface 11c is formed at a distal end of the incomplete insertion-detecting projection 11b at an outer surface thereof. A slanting guide surface 19a for the slanting abutment surface 11c is formed at a front end of a housing wall 19 of the terminal receiving chamber 9 having an elastic retaining piece portion 14 formed thereon. The examination pin D' is supported at its proximal end portion so as to be tilted relative to the examination terminal 10 in a direction intersecting the axial direction, and the slanting abutment surface 11c is abutted against the slanting guide surface 19a so that the examination pin can be positively guided into a flexure space 16 for the elastic retaining piece portion 14 within the housing.
For effecting the examination, the operating lever 5 (FIG. 4) is pivotally moved to advance the examination instrument body 3, so that this body 3 receives a front portion of the connector B therein, and the head 11' of each examination pin D' is brought into contact with an associated metal terminal C. In FIG. 6, the metal terminal C in the lower terminal receiving chamber 9 in the connector B is completely inserted, and a retaining projection 14a of the elastic retaining piece portion 14 is fitted in a retaining hole 15 in the metal terminal C, and therefore the elastic retaining piece portion 14 is completely restored into its original condition. However, the metal terminal C' in the upper terminal receiving chamber 9 is incompletely inserted, and the elastic retaining piece portion 14 is kept displaced downwardly through the retaining projection 14a.
When the connector B in this condition is examined, the incomplete insertion-detecting projection 11b of the examination pin D', corresponding to the metal terminal C, enters the flexure space 16 for the elastic retaining piece portion 14, so that the conducting contact surface 11a contacts the distal end of the metal terminal C, thereby conducting an electric circuit for examination purposes. However, the incomplete insertion-detecting projection 11b of the examination pin D', corresponding to the upper metal terminal C', abuts against the distal end of the elastic retaining piece portion 14, so that the advance of the examination pin D' is prevented, and the conducting contact surface 11a is held out of contact with the metal terminal C'. Therefore, an electric circuit for examination purposes is not in a conducting condition, and this incomplete insertion is judged by the checker.
In the above conventional connector examination instrument A', the conducting contact surface 11a for abutment against the distal end of the metal terminal C', as well as the incomplete insertion-detecting projection 11b for abutment against the elastic retaining piece portion 14, is formed integrally with the shank 11e of the examination pin D', using electrically-conductive metal. Therefore, when the examination pin D' is inserted obliquely as shown in FIG. 7, the incomplete insertion-detecting projection 11b is brought into contact with the metal terminal C', thus causing a detection error.